package cn.com.b2office.struts2.action;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.net.URLDecoder;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import cn.com.b2office.util.DES;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

/**
 * @author  zhenggang
 * @version Jul 16, 2008 10:58:56 AM
 * comment
 */
public class CreateVerifyCodeAction extends ActionSupport {

	private static final long serialVersionUID = -1708564526707474888L;

	private String randNum;    // 页面请求传来的随机数
	private ActionContext ctx = ActionContext.getContext();
	private HttpServletResponse response;
	private BufferedImage image;
	private DES des = new DES();
	
	public String execute()throws Exception{
		response = ServletActionContext.getResponse();
		// 设置浏览器不缓存此图片   
		response.setHeader("Pragma", "No-cache");   
		response.setHeader("Cache-Control", "no-cache");   
		response.setDateHeader("Expires", 0);  
		//System.out.println("in CrateVerifycodeAction ,randNum= "+randNum);
        //=======================================================================================
		// 在内存中创建图象
		int width = 60, height = 20;
		image = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);
		// 获取图形上下文
		Graphics graphic = image.getGraphics();
		// 设定背景色
		graphic.setColor(getRandColor(200, 250));
		graphic.fillRect(0, 0, width, height);
		// 设定字体
		graphic.setFont(new Font("Times New Roman", Font.PLAIN, 18));
		// 画边框
		// g.setColor(new Color());
		// g.drawRect(0,0,width-1,height-1);
		// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
		graphic.setColor(getRandColor(160, 200));
		// 生成随机类
		Random random = new Random();
		for (int i = 0; i < 155; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int xl = random.nextInt(12);
			int yl = random.nextInt(12);
			graphic.drawLine(x, y, x + xl, y + yl);
		}
		//================================================================
		// 取随机产生的认证码(4位数字)
		//String sRand = "";
//		randNum = URLDecoder.decode(randNum, "utf-8");
//		System.out.println("in CreateVerifyCodeAction, 解密前 randNum = "+randNum);
//		randNum = des.getDesString(randNum);
//		System.out.println("in CreateVerifyCodeAction, 解密后 randNum = "+randNum);
		for (int i = 0; i < randNum.length(); i++) {
			//String rand = String.valueOf(random.nextInt(10));
			//sRand += rand;
			// 将认证码显示到图象中
			graphic.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
			graphic.drawString(String.valueOf(randNum.charAt(i)), 13 * i + 6, 16);
		}
		
		// 图象生效
		graphic.dispose();	
		ImageIO.write(image, "JPEG", response.getOutputStream());
		
		return null;
		
	}
	public Color getRandColor(int fc, int bc) {// 给定范围获得随机颜色
		Random random = new Random();
		if (fc > 255)
			fc = 255;
		if (bc > 255)
			bc = 255;
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	public void setRandNum(String randNum) {
		this.randNum = randNum;
	}
}
